Method for assembling groups of flat modular pieces

ABSTRACT

A method for assembling groups of generally flat modular pieces such as ceramic tile into structurally unitary multi-unit assemblies. The pieces are arranged in groups each having a desired configuration and orientation of desired area and shape with desired inter-piece spacing. The group of pieces is placed on an assembly plane with their rear faces turned upwardly. A plurality of discrete masses of binding medium is placed on the adjacent edges of the pairs of pieces in the group and overlying the inter-piece spaces. The masses of binding medium are pressed flat in a direction normal to the plane of the front faces of the pieces to squeeze some of the binding medium into the inter-piece spaces and against the edges of the backs of adjacent pieces. The binding medium is then set up to bond the pieces to each other and to form a unitary multi-piece assembly.

United States Patent Jackson [4 1 Apr. 25, 1972 54] METHOD FOR ASSEMBLING GROUPS FOREIGN PATENTS 0R APPLICATIONS OF FLAT MODULAR PIECES 266,404 ll/l968 France ..52/3s9 [72] inventor: Robert C. Jackson, Florence, Ala. Primary Examiner Carl D. ouarfonh [73] Assignee: Stylon Corporation, Florence, Ala. Ass-[ mm Ex miner-E. E. Lehmann [221 Filed: Apr. 14, i969 21; Appl. No.: 815.647 [57 ABSTRACT A method for assembling groups of generally flat modular l l Cl /389, l5 /2 pieces such as ceramic tile into structurally unitary multi-unit 156/304 assemblies. The pieces are arranged in groups each having a [5 l I Int. (J. .1504! 13/08, B32b 7/l4 desired configuration and orientation f desired area and l Field 59am l 56/2901 shape with desired inter-piece spacing. The group of pieces is 1 289; 52/387 389 placed on an assembly plane with their rear faces turned upwardly. A plurality of discrete masses of binding medium is [56] Rem'mces Cited placed on the adjacent edges of the pairs of pieces in the group UNITED STATES PATENTS and overlying the inter-piece spaces. The masses of binding medlum are pressed flat in a d1rect1on normal to the plane of 3,463,695 3/1969 schwelkel et a] x the front faces of the pieces to squeeze some of the binding 3,322,591 5/1967 C y "156/551 x medium into the inter-piece spaces and against the edges of 3,041,785 7/ 1962 MacDmlald er "52/389 x the backs of adjacent pieces. The binding medium is then set 3,319,392 5/1967 Fitzgerald ..52/389 up to bond the pieces to each other and to form a unitary multi-piece assembly.

8 Claims, 20 Drawing Figures Patented April 25, 1972 3,658,621

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METHOD FOR ASSEMBLING GROUPS OF FLAT MODULAR PIECES BACKGROUND OF THE INVENTION Flat modular pieces of various materials, particularly ceramic tile and the like, as used on floors and walls, has been set in cement or by adhesive on the surface to be covered since ancient times. For many centuries, each individual tile was manually placed and great care had to be taken to maintain the desired patterns and spacing between the individual tiles.

In the relatively recent past, groups of pieces of ceramic tiles have been mounted on sheets of paper which were adhered to their front faces in order to permit the placement of numbers of pieces simultaneously. For examples, sheets of paper two or more square feet in size were adhered to a corresponding number of tile pieces, say I in. X 1 in. or 144 to the square foot, or to smaller numbers of larger 4 in. X 4 in. tiles or 6 in. X 8 in. tiles or combinations of various sizes. This system left the back surfaces of the tiles completely exposed for best adhesion to the cement bed or the other surface but, by covering the front surfaces, made it difficult to be sure that the pattern and spacing were correct.

Later the idea of adhering perforated sheets of paper to the back surfaces was developed. This permitted the fronts of the tiles to be observed while setting the tiles but severly reduced the exposed areas of the back surfaces of the tiles and thus lessened the degree of adhesion to the bed or surface.

Still later, open mesh fabric or open mesh screenlike materials, some having openings as large as in. X in., were adhered to the back surfaces to reduce the covered area of the backs of the pieces and thus to improve the adhesion of the multi-unit assemblies.

However all of front paper mounted, back paper mounted and mesh or screen mounted assemblies in common have the fault that, while preventing separation of the pieces from each other, they do not provide for maintaining the tiles in desired spacing from each other.

Secondly all of the paper and mesh or screen mounted tiles have a considerable area of their back sides covered and thus have less than desirable areas exposed for adhesion.

In addition because of the flexibility of the paper or mesh, such assemblies do not possess any panel-like or board-like stiffness so they are difficult to emplace on vertical surfaces such as walls. Even more importantly, however, the flexibility of the paper or mesh results in the adjacent tiles being free to move toward each other unless the assembly is stretched taught. This often results in irregular inter-tile or grouting spaces and in engagement of the tile pieces with each other with resulting damage to the edges or corners of the tile pieces.

In attempts to overcome these many difficiencies it has been suggested that the tile pieces be connected by small wooden discs adhered to their rear surfaces or by small discrete drops of resinous material placed at their corners and adhered to the edges of adjacent tiles. Such systems require the careful positioning of a large number of small individual discs or drops of resin and registration became a serious problem.

, SUMMARY OF THE INVENTION The method of the invention is an improvement over methods previously suggested for assembling groups of pieces, such as tiles, to each other, to form structurally integral multiunit assemblies each of which can be handled as a boardlike structure and in which the tiles are held firmly to each other in selected spacing, whether in actual contact or not. The method of the invention is much simpler and much less expensive to practice than previously suggested methods for fabricating such assemblies.

The method of the invention comprises the steps of assembling the-selected modular group of complementary pieces of tile in the desired number, arrangement, configuration and spacing with their front faces (i.e., those later to be exposed) lying in a common plane. Masses of binding medium having widths enough to span the inter-tile spaces and contact only the edges of the back faces, and lengths less than the lengths of adjacent edges of the tiles are placed on the tiles in a pattern corresponding to and overlying the inter-tile spaces, preferably extending along the sides of the tiles and having lengths less than the corresponding edges of the tiles.

The binding medium is somewhat viscous so that it does not freely run down into the inter-tile spaces but remains in substantially bridging relationship thereto. However, the binding medium, which preferably is self curing at atmospheric exposure and temperature, is soft enough so that the masses of resin are flattened by being pushed simultaneously by an interplane toward the plane of the front faces of the pieces of tile to squeeze part of each mass into its respective inter-tile space, to positively adhere the binding medium to the rear surfaces of the edges of the tiles and to portions of their edges and to flatten the backs of the masses into a plane parallel to and spaced from the plane of the front faces of the tile pieces.

A vertical stack of groups of tile pieces with inter-leaved, flat inter-planes such as sheets of compressed hardwood fiber board, such as Masonite, is built up, with successive groups of tile pieces being positioned for reception of the binding material by a partial perimeter fence to insure registration of the masses of binding medium with the respective inter-tile spaces. The superposed layers apply pressure to the preceding assemblies during the carrying out of the subsequent curing of the binding medium.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in front perspective of an apparatus for carrying out the method according to the invention;

FIG. 2 is a rear view of the apparatus illustrated in F IG. 1, shown on an enlarged scale, with parts broken away and parts shown in phantom;

FIG. 3 is a fragmentary front view of some of the apparatus illustrated in FIGS. 1 and 2 and shown on a scale slightly larger than FIG. 2;

FIG. 4 is an enlarged, fragmentary vertical sectional view taken along the line 4-4 of FIG. 3;

FIG. 5 is a fragmentary view, partly in section and partly in elevation, taken from the position indicated by the line 5-5 of FIG. 3 with some parts broken away and some shown in phantom;

FIG. 6 is a fragmentary, vertical sectional view taken along the line 6-6 of FIG. 5 and shown on an enlarged scale;

FIG. 7 is a fragmentary, vertical sectional view taken along the line 7-7 of FIG. 5;

FIG. 8 is a still further enlarged, fragmentary view, partly in elevation and with parts broken away, illustrating how a series of assemblies of modular pieces are produced according to the invention;

FIG. 9 is a fragmentary, vertical sectional view taken along the line 9-9 of FIG. 8 and shown on an enlarged scale;

FIG. 10 is a fragmentary isometric view, with parts broken away, illustrating how modular pieces are assemblied to each other according to the method of the invention;

FIG. 11 is an exploded isometric view showing a manifold by which binding medium is emplaced on a group of tile pieces according to the invention;

FIG. 12 is an isometric view showing a group of tile pieces as assembled according to the invention;

FIG. 13 is a fragmentary, vertical sectional view taken along the line 1313 of FIG. 10 and showing the elements of the manifold plate in their assembled condition as engaged with a portion of a group of tiles shown in FIG. 12;

FIG. 14 is'a fragmentary view taken along the line l414 of FIG. 13 and showing the under side of the manifold plate illustrated in FIG. 11 on an enlarged scale;

FIG. 15 is a fragmentary vertical sectional view taken along the line 15-15 of FIG. 14 and, again, shown on an enlarged scale;

tion, with parts broken away, taken from the position indicated by the line 18-18 of FIG. 17;

FIG. 19 is a fragmentary end view taken from the position indicated by the line 19-19 of FIG. 17; and

FIG. 20 is a fragmentary vertical sectional view taken along the line 20-20 of FIG. 18.

DESCRIPTION OF THE PREFERRED EMBODIMENT A method according to the instant invention for assembling a plurality of groups of flat modular pieces into multi-unit assemblies will be described as carriedout upon illustrative apparatus by which multi-unit sheets, each consisting of twelve individual pieces of tile, each tile measuring approximately 4% in. X 4% in., is carried out. It will be appreciated, of course, that the method of the invention may. be employed for the assembly of multi-unit groups of flatpieces other than ceramic tiles and also for the assembly of multiple unit groups of pieces of ceramic tiles having dimensions either larger or smaller than 4% X 4%". In such changes, of course, the means for placing the masses of binding medium along and bridging the inter-tile or inter-piece spaces would be so designed and arranged as to register with these inter-tile or inter-piece spaces thereby providing for the placement of the masses of binding medium appropriately to bridge such spaces between. the tiles or other pieces of different sizes and in different groups. While the method embodying the invention will be illustrated for the assembly of rectangular groups of rectangular pieces it will also ,be appreciated that by appropriate changesin the design of various component parts of an apparatus to carry out the method, the method. may be employed for the assembly of groups of tile pieces having overall oval patterns, modular patterns with irregular sides, modular patterns of which the sides meet at other than 90 angles, etc. The arrangement of the apparatus readily can be varied to accommodate modular groups having virtually any planned configuration and comprising any selected number of individual'pieces which are arranged complementary to each other, whether or not all of the pieces are of the same dimensions or of the same shapesor sizes.

Apparatus upon which the method of the inventionreadily may be carried out is illustrated, in part, in FIG.- 1 where a table 20 is shown as erected upon legs 21 that in turn are. mounted upon a base 22. The base 22 is illustrated as having large casters 23 so that it can be moved. For example, the

basic apparatus for assembling groups of tiles may be thus moved to a different location where tiles of different sizes or shapes are being produced or are to be packaged for shipment.

The table 20 supports a flat plate 24 which functions as an assembly base plane in carrying out the method of the invention and, in this structure for the assembly of rectilinear groups of tile pieces, there are two boundary plates 25 and 26:

which extend vertically upwardly above the table 20 and intersect each other at a right angle because the apparatus is designed to assemble rectilinear groups of tiles. A number of such assemblies or groups of modular tile pieces are indicated by, the reference number 27 and a previously assembled plurality of groups of such tiles are indicated by the reference number 28 and shown stacked on a base plane or plate 24a.

Each of the groups of tiles, for example the individual group 29, consists of twelve 4% X 4%" ceramic wall tiles. It will be appreciated, of course, that were the method'of the invention being employed for the assembly of groups of other sizes or shapes of tiles, the numbers of pieces and their arrangement would determine the shape and extent of the base plane plate 24 and the boundary plates 25 and 26 or, possibly, a single boundary plate having a curved profile by which the margins of groups of tiles which were not rectilinear would be established and maintained.

The plate 24 which forms the assembly base plane for the groups of tiles indicated by the reference number 27, rests in assembly position upon a number of parallel conveyor rollers 30 which are mounted in the table 20 and after a number of groups 29 have been superposed one upon the other to a height determined by physical size of the apparatus, the entire stack of groups such as the stack 28 is moved along the rollers 30 still riding upon its assembly base plate 24a and over onto a roller conveyor generally indicated by reference number 31.

As can be seen by reference to the stack 28, and particularly to the uppermost group of tiles 29, in carrying out the method of the invention each group of tile pieces consists of twelve individual tiles 32 which are retained as a group by individual masses 33 of suitable binding medium. Each of the masses 33 extends along portions of the adjacent back surfaces of the adjacent tiles 32 and at least partially along and across the space between the edges of the individual tile pieces 32 which are normally referred to as grouting spaces." In carrying out the method of the invention all of the masses 33 by which the 12 tile pieces 32 are unified into a group 29, are deposited or placed simultaneously by a suitable manifold mechanism, generally indicated in FIG. 1 by the reference 34, which is supported by and movable vertically in a framework, generally indicated by the reference number 35.

Referring now to FIG. 2, the framework 35 is erected on a post 36 welded to and mounted by a plate 37 having support wings 38. The post 36 also functions to hold the boundary plates 25and 26 in position overlying the assembly table 20, by means of horizontal angle braces 39 secured to the post 36 and to which the boundary plates 25 and 26 are attached. (See also FIG. 5)

A heavy horizontal arm 40, illustrated as being a heavy tube similar to the tube from which the post 36 is fabricated, is welded at the upper end of the post 36 and extends forwardly, overlying the space defined by the boundary plates 25 and 26. A heavy plate 41 extends longitudinally along and is welded to the upper surface of the arm 40 and a cross angle 42 is welded to the under side of the am. 40 at its front end, extending transversely thereof. A lower cross plate 43 (See also FIG. 3) is rigidly attached, as by welding or bolting, to the cross angle 42 and a similar upper cross plate 44, along with vertical side plates 45 and 46, completes an open rectangular frame for the support and guidance of the manifold mechanism 34. Two parallel wings 47 are welded to the outer vertical edges of the side plates 45 and 46 and extend rearwardly therefrom for bracing the structure and for the mounting of various mechanisms to be described later.

Two pairs of roller guides 48 (FIGS. 3 and 6) are adjustably mounted on the upper and lower cross plates 43 and 44. Each of the roller guides 48 comprises a generally circular base plate 49 in which there is set a pair of spaced, parallel studs 50. The front or outer ends of the studs 50 are tied together by a cross bar 51. A grooved roller 52 is rotatably journaled on each of the studs 50. The base plate 49 has circumferentially extending slots 53 near its periphery and machine screws 54 extend through the slots 53 and into the cross plate 43 or 44. Each pair of roller guides 48 serves to guide the vertical movement ofa guide rod 55 and each of the roller guides 48 may be adjustably rotated on an axis, centrally of and parallel to the studs 50, in order to properly embrace the respective guide rod 55 between the pair of grooved rollers 52 of that roller guide 48.

The lower ends of the guide rods 55 are socketed into retaining blocks 56 (FIGS. 5 and 11) being held therein by pins or set screws 57 and the two retaining blocks 56 are secured to pads 58. The pads 58, in tum,.are attached to the upper surface of a top plate 59 of a manifold 60 that is shown in exploded perspective in FIG. 11.

The weight of the manifold 60 and its guide rods 55 is balanced by a counter-weight 61 (FIG. 5) located interiorly of the hollow support post 36 and connected to the manifold 60 by a flexible cable 62. The cable 62 is tied to an eye 63 that is screwed into the upper end of a T-fitting 64 threaded into a manifold inlet 65 at the center of the top plate 59. The cable 62 passes over a pair of pulleys 66 which are mounted at the upper corners of the vertical plate 41.

A T-bar 67 is welded to the upper edge of the plate 41 and extends vertically therefrom parallel to the guide rods 55 and located in the medium plane therebetween, and also is welded to a pad 68 and through the pad 68 secured to the upper cross plate 44. At the upper end of the T-bar 67 there is a rigid, horizontal arm 69 extending forwardly therefrom and a heavy clevis 70 is attached to the under side of the horizontal flange of the arm 69 at its forward end. A valve housing 71 has an ear 72 extending between the arms of the clevis 70 and is suspended therebetween on a clevis pin 73. The valve housing 71 also functions as an upper end for a vertically oriented hydraulic cylinder 74 which moves the manifold 60 up and down to deposit or place successive charges of binding medium on the back surfaces of a group of individual tiles 32.

A piston 75 and piston rod 76 are located within the hydraulic cylinder 74. The lower end of the piston rod 76 extends out of the cylinder 74 through a gland 77 (see also FIG. 4) and its lower end is threaded into a heavy nut 78 that is welded onto the top plate 59 of the manifold60. A lock nut 79 is also threaded on the rod 76 to tightly retain it in the nut 78. A shock absorbing spring 80 is located circumjacent the rod 76, extending between a washer 81 which rests on the lock nut 79 and a washer 82 compressed upwardly against the under side of the gland 77. A cushioning ring 83 formed of rubber or similar resilient material extends around the coils of the spring 80 between the two washers 81 and 82.

When the piston 75 is moved to the upper end of the cylinder 74, raising the rod 76 and lifting the manifold 60, the washer 82 first engages the under side of the gland 77 (in the position shown in FIG. 4). As the rod 76 continues to be pulled upwardly, the spring 80 is compressed and the upward movement slowed down. The final shock is absorbed by the ring 83 when in the position indicated in dotted lines in FIG. 4.

Movement of the piston 75 and the manifold 60 between its uppermost and lowermost positions (shown in solid lines and dotted lines, respectively, in FIG. 5) is under the control of a valve 84 (FIG. 7) located within the valve housing 71. The

valve 84 comprises a slider 85 that is yoked to a stem 86 and is movable between the position shown in FIG. 7 and a position to the right thereof, by a solenoid 87. In the position shown in FIG. 7 high pressure hydraulic fluid enters the valve housing 71 from a port 88, flows around the stem 86 and out through a port 89 to a hydraulic line 90 to the bottom of the cylinder 74. This moves the piston 75 upwardly and raises the manifold 60 to the uppermost position. Exhaust fluid flows from the space in the cylinder 74 above the piston 75 through an exhaust port 91 and the slider 85 to an exhaust line 92. When the valve is reversed i.e. the slider 85 moved to the right in FIG. 7, high pressure fluid flows from the port 88 around the slider 85 then through the port 91 into the space in the cylinder 74 above the piston 75. Similarly, at this point, fluid beneath the piston 75 is exhausted through the hydraulic line 90 and the port 89 into the interior of the slider 85 and thence to the exhaust line 92.

A hydraulic line 93 is connected into the cylinder 74 above the uppermost position of the piston 75 and communicates with a pressure responsive switch 94 which functions to reverse the solenoid 87 at the bottom of the stroke of piston 75 The manifold 60 comprises several assembled plates including the top plate 59 (FIG. 11), an intermediate distribution plate 95 and an orifice plate 96. The three plates 59, 95 and 96 are assembled to each other as a unitary structure by means of socketed machine screws 97 and 98 (see FIG. 13, for example). As earlier mentioned, the top plate 59 has a central inlet 65 into which the T-fitting 64 is threaded. A source line 99 for the binding medium is also connected by the T-fitting to the central inlet 65.

The binding medium from which the individual tile binding masses 33 are formed, may be any one of a variety of adhesive materials which (1) set up upon exposure to atmospheric conditions, (2) require the admixture of components in their initial preparation, (3) require heat in order to be set up. Preferably, however, the binding medium is an adhesive which remains fluid when under pressure or when isolated from atmosphere and which sets up to a condition of some flexibility and toughness shortly after exposure to atmosphere. Any such binding medium, regardless of its nature, must have the capacity to tightly bond to the surfaces of the ceramic tile pieces 32 and to resist deterioration from atmosphere, setting beds or tile setting adhesives. In carrying out the method according to the invention, a binding medium may be used which is generally identified as a one-component room temperature vulcanizing silicone rubber. Such adhesives are commercially available from several sources, including Dow-Corning Corp. and-General Electric Company under such designation. Such adhesives remain fluid although quite viscous when enclosed in containers or lines where no exposure to atmosphere occurs and set up rather rapidly after deposition on the back faces of the individual tile pieces 32 according to the invention without the addition of heat from outside sources.

The method of the invention may also be carried out utilizing other adhesives. For examples, two component R T V silicone rubbers, or polyvinyl chloride plastisols, with subsequent heat treatment as necessary.

The binding medium or adhesive supplied from the source line 99 in response to pressure from metering mechanism to be described below, flows through the inlet orifice 65 in the top plate 59 into a distribution channel 100 illustrated as having a main central portion 101 and six side channels 102 each of which terminates in an orifice 103. The orifices 103 in the distribution plate 95 lead to multi-branch channels 104 and 105 and to a cross channel 106 milled in the surface of the orifice plate 96.

Each of the channels 104 has three side channels 107a, 107b and 1070 and each of the channels 105 has four side channels 108a, 108b, 1086 and 108d. The cross channel 106 is aligned with two orifices 103 in the distribution plate 95 and extends continuously across the orifice plate 96. Each of the side channels 1070, 107b and 107e, and 108a, 108b,-1080 and 108d leads to a single injection orifice 109 and the cross channel 106 leads to three injection orifices 110 which are located one at each end and one at the center of the orifice plate 96. Each of the injection orifices 109 and 1 10 supplies adhesive or binding medium to an individual nozzle 1 11 shown in detail in FIGS. 15 and 16.

Each of the individual nozzles 111 places or deposits one of the individual masses 33 of binding medium in the respective position illustrated in FIG. 12, wherein one of the tile groups 29 is shown in place on its base plate 24 with the front faces of the tile pieces 32 all lying in the assembly base plane determined by the plate 24 and with the back surfaces of the individual tile pieces 32 all turned uppermost for the reception of the individual masses 33 of binding medium. In FIG. 12 one group of individual masses of resin 33 is designated as 33a, 33b, 33c, and 33d to indicate the masses of resin 33 that are placed upon the back surfaces of four adjacent tile pieces 32 by the nozzles 111 fed from the channels 1080, 108b, 108c and 108d, respectively, in the orifice plate 96.

Each of the nozzles 111 (see particularly FIGS. 15 and 16) consists of two machined blocks 1 12 and 113 which are identical and which are held together to form a single nozzle 111 by several machine screws 114. The blocks 112 and 113 form opposite sides of a flared entry opening 115 which terminates in a narrow elongated slot 116 that leads, in turn, to an elongated generally cylindrical chamber 117. The chamber 117 opens through a narrow elongated slot 118 to an outwardly flared and elongated deposition groove 119. The deposition groove 119 is formed by two flat milled surfaces cut in the inner lower comers of the blocks 112 and 113 which terminate in sharp apices 120 and the material of the blocks 112 and 113 is milled away along the outer sides of the apices 120 to minimize the likelihood of the binding medium spreading beyond the margins of the grooves 119 defined by the apices 120. By the alternate restriction in the slots 116, expansion in the chambers 117, restriction through the slots 118 and expansion in the grooves 119, the adhesive binding medium is caused to mix and flow in controlled pattern. This insures that the fluid medium does not merely flow through the central parts of the nozzles 111 but is evenly spread out in the grooves 1 19 so as to deposit a uniform mass all along their lengths and, therefore, all along the lengths of the masses 33.

As can best be seen by reference to FIG. 15, a charge of the binding medium of sufficient volume to form all of the masses 33 for a single group 29 of tiles 32 is forced through the plates 59, 95 and 96 and through all of the nozzles 111 each time the medium feeding mechanism is actuated. The manifold 60 is moved downwardly and the nozzles 111 contact the back surfaces of the tile pieces 32, so that a mass 33 of medium is placed on adjacent edges of the tile pieces 32 so as to bridge across the inter-tile spaces, to penetrate slightly into the intertile spaces between tile spacing lugs 126 and to partially fill such spaces with protrusions 126a of binding medium in order to bond the adjacent tile pieces 32 to each other. The shock of engagement of the bottom faces 121 of the nozzles 111 with the backs of the tile pieces 32 is absorbed by a plurality of resilient cushioning blocks 122; which are interspersed between the nozzles 111 and extend slightly therebeyond. The cushioning blocks 122 may be adhered or otherwise secured to the underface of the orifice plate 96 and the individual nozzles 111 are mounted on the under side of the orifice plate 96 by heavy machine screws 123.

It will be observed in FIG. 15, forexample, that the back faces of the tiles 32 have ribs 124 with which the bottom faces 121 of the nozzles 111 actually come into contact at the time of deposition of the binding medium masses 33. It will be appreciated that if the method of the inventionis being utilized for the assembly of groups of tile pieceswhich do not have ribs on their back surfaces then the bottom faces 121 of the nozzles 111 and the bottom faces of the cushioning blocks 122 would come directly into engagement with the'flat back surfaces of the tile pieces.

In carrying out the method of the invention, the base plate 24 is first positioned on the rollers 30 of the table 20 (FIGS. 8-10), being pushed against the two boundary plates 25 and 26. A group of twelve individual tiles 32 is collected or assembled on a carrier plate 125 and the carrier plate 125 is then moved onto the base plate 24 and urged over until the edges of the tile pieces 32 engage the boundary plates 25 and 26. In the assembly of groups of 4 /4 in. X 4% in. wall tiles, according to the invention, the actual engagement between the individual tile pieces 32 takes place by the engagement of their spacing lugs 126 which maintain the inter-tile or grouting spaces between the individual tiles 32. Of course, if tiles other than the type equipped with spacing lugs 126 are being assembled according to the invention, the upper surface of the carrier plate 125 would be provided with a suitable grid work or other conventional means to assure the correct spacing of the individual tile pieces relative to each other.

In any event, after the group of tile pieces 32, for example, the twelve pieces forming the group 29, has been positioned accurately by the boundary plates 25 and 26, the operator actuates a push button 127 (FIGS. 3 and This energizes the solenoid 87-to shift the valve 84 to admit hydraulic fluid to the upper end of the cylinder 74 and moves the manifold 60 downwardly until its nozzles 111 and cushioning blocks 122 engage the rear surfaces of the tile pieces 32. By a previous actuation of the mechanism which is described below, the deposition grooves 119 of the nozzles 111 have been filled with the binding medium.

During the short time while the binding medium is being deposited, hydraulic pressure builds up in the cylinder 74 above the piston 75 and pressure delivered through the hydraulic line 93 actuates the pressure responsive switch 94. This reverses the action of the solenoid 87 moving the slider 85 of the valve 84 to the left position (FIG. 7) and admitting hydraulic fluid to the lower end of the cylinder 74 to raise the manifold 60 to its upper position.

When the manifold 60 is raised upwardly away from the surfaces of the tile pieces 32, the individual masses 33 of binding medium cling to the tile surfaces and are pulled out of their respective deposition grooves 119 to lie on the rear surfaces of the tile pieces 32 in slightly mounded, elongated shapes. The binding medium should be viscous enough so that it does not freely run down between the edges of the tile pieces 32 but remains in mounded, bridging relationship thereto, contacting the back surfaces of the tile pieces 32 alongtheir edges.

While the manifold 60 is moving upwardly. the operator lays a sheet 128 of a thin flexible material over the masses of resin 33. The sheet 128 must be non-wettable by the adhesive constituting the masses 33 and of material to which the adhesive will not adhere.

When the manifold 60 reaches the top of its stroke, the operatoractuates the mechanism for metering the binding medium into the deposition grooves 119. As will be explained below, some small period of time is required to force the viscous medium through the manifold 60 and into the grooves During the metering time, the operator places a subsequent tile group 29 and its carrier plate on the intervening sheet 128. The weight of the new tiles in the tile group 29 and of the carrier plate 125 starts to compress the masses 33 of binding medium on the lower group of tiles, progressively forcing adhesive protrusions 126a into the spaces between the tiles and intermediate the spacing lugs 126. The operator squares up and nests the tile pieces 32 adjacent each other in the appropriate arrangement and once again actuates the push button 127 to cause the manifold to be fed downwardly in order to deposit a group of masses 33 of the binding medium or adhesive on the backs of the tiles in this second tile group 29.

' A Because reversal of the direction of movement of the valve 84 results from pressure build-up as explained above, each successive cycle of the manifold moving cylinder 74 results in pressing the bottom faces 121 of, the nozzles 111 and of the cushioning blocks 122 against the back surfaces of tiles in the second and subsequent tile groups 29 with the same pressure as the stack of tile groups 29 builds up. When the stack of tile groups 29 has built up to a considerable height, as illustrated,

for example, in FIG. 3, where such a stack 28 is shown with its interleaved tile groups 29, non-wettable sheets 128 and carrier plates 125, the operator places a top non-wettable' sheet 128 on the back of the uppermost tile group 29 and then lays a heavier plate 129 atop the stack 28 to continue to maintain pressure on the masses 33 of binding medium in the uppermost group 29.

The binding medium is supplied to the manifold 60 through a system and mechanism shown in FIGS. 2 and 5. A can 130 containing the binding medium is removably positioned upon a plate 131 which forms a base for an adhesive pump mechanism generally indicated by the reference number 132. The pump mechanism 132 comprises a tripod consisting of two bracing rods 133 and a vertical piston rod 134 all of which are secured at their lower ends in the plate 131 and connected at their upper ends by a cross brace 135. The piston rod 134 carries a piston 136 located interiorly of a double acting cylinder 137 which is located circumjacent the piston rod 134. A four-way valve 138 is connected to the cylinder 137 and to an air line 139 fed by a pressure air line 140 from an air comv pressor 141 which is also mounted upon the base 22.

A pump support arm 142 extends rearwardly from the upper end of the cylinder 137 and is clamped to a tubular conduit 143 that extends vertically parallel to the piston rod 134. The lower end of the tubular conduit 143 carries a double acting pump 144 which has a pump rod 145 extending upwardly through the conduit 143 and through a gland 146 at the upper end of the conduit 143. The pump rod 145 is accessable through an open casting 147 erected on the top of the gland 146 and supporting a vertically oriented pump actuating cylinder 148. The cylinder 148 has a piston 149 on the upper end of the pump rod 145. The pressure air line 140 is connected through a pressure regulator 150 to the pump cylinder 148. The pump cylinder 148 is internally valved (not shown) and the pump 144 so designed that as long as air under pressure is admitted to the pump cylinder 148 and the output from the pump is at a lower pressure, the piston 149 is reciprocated in the cylinder 148 to pump the binding medium or adhesive out of the supply in the can 130. I

A flexible, air-sealing diaphram 151 is secured to the lower surface of the pump 144 and is of such diameter as to seal against the wall of the can 130. When the can 130 is to be placed on the plate 131, the operator actuates the valve 138 to admit air to the top of the cylinder 137 which causes the cylinder 137 to be moved upwardly on the piston rod 134 raising the conduit 143 and associated mechanism including the pump 144 and the diaphram 151. When the cylinder 137 reaches the top of its stroke, the operator centers the valve 138 to hold the mechanism carried thereby at its upper position. The operator then places a can 130 of the binding medium into position and reverses the four-way valve 138 to supply air under pressure to the cylinder 137 beneath the piston 136. This forces the cylinder 137 and the conduit 143, pump 144 and diaphram 151 downwardly into the interior of the can 130 until the sealing diaphram 151 engages the top surfaces of the adhesive or binding medium in the can 130. The diaphram 151 is so designed as to maintain an air seal around its perimeter. The air pressure fed to the cylinder 137 is of such force as to maintain the diaphram 151 in contact with the upper surface of the adhesive so that as the level of the adhesive in the can 130 lowers, the diaphram 151 and pump 144 move downwardly therewith until the bottom of the can 130 is reached. At this point, an adjustable stop 152 carried by the cylinder 157 engages a limit switch 153 and rings a bell 154 or energizes some other audible or visible signal to tell the operator that the can 130 is empty. 7

The output from the pump 144 flows upwardly through the tubular conduit 143 around the pump rod 145 until it reaches the gland 146 whence it flows through an adhesive feed line 155 to a metering control valve 156 mounted on one of the wings 47 near the front of the machine with its handle 157 accessable to the operator. The four-way valve 156 is connected to both sides of a metering cylinder 158 (FIG. and to the source line 99 through the manifold 60. Binding medium or adhesive under pressure is fed through the feed line 155 to the metering valve 156 and, in the position illustrated in FIG. 5, for example, flows through a line 159 to one end of the metering cylinder 158. A free piston 160 is located interiorly of the metering cylinder 158 and is movable back and forth between two positions determined by stop screws 161 that are threaded through opposite ends of the metering cylinder 158. As the adhesive or binding medium flows into one end of the metering cylinder 158 it forces the piston 160 toward the other end of the metering cylinder 158 and extrudes a previously metered charge of adhesive or binding medium out of the metering cylinder 158 through a connection line 162 and the other side of the metering control valve 156 to the line 99.

On the next operation, the operator swings the handle 157 downwardly, reversing the connections in the metering control valve 156, so that the adhesive under pressure in the line 155 flows through the control valve 156 and the connection line 162 to the right side of the metering cylinder 158, forcing the previously metered charge out of the left side of the metering cylinder 158 and through the line 159 and the control valve 156 to the source line 99. The operator shifts the metering control valve 156 from one of its positions to the other of its positions immediately after the manifold 60 reaches the top of its stroke so that the metering action can be completed be fore the next down stroke.

With further reference to FIG. 2, the high pressure port 88 of the valve 84 (see FIG. 7) is connected by a high pressure hydraulic line 163 to the output side of a motor driven pump generally indicated by 164 and the exhaust line 92 from the valve 84 is connected by an exhaust line 165 to an oil reservoir 166 for the pump 164.

FIGS. 17-20 are somewhat diagramatic illustrations of tile feeding systems and conveyor lines whereby the method of the invention may be automated to a considerable extent and the tile groups 29 i.e. the sheets of tile suitable for setting are produced according to the invention at a high rate with a minimum of personnel.

FIG. 17 is a simplified plan view including the table 20, its base 22, the boundary plates 25 and 26 and the table rollers 30. A tile group 29 is shown in place in the area defined by. the boundary plates 25 and 26 and the air compressor 141, hydraulic fluid pump 164, binding medium can 130 and post 36, are also shown in order to orient the apparatus described above to the apparatus illustrated in FIG. 17.

An operator positioned at the point indicated by the block No. I in FIG. 17 unloads individual tiles 32 from a bulk tile supply generally indicated by the reference number 167 and places them on edge in three parallel guide chutes 168 which extend along and are part of a tile supply table generally indicated by the reference number 169. Each of the chutes 168 has a pair of spaced parallel feeding belts 170 upon which the individual tiles 32 are rested on edge and which gradually feeds the tiles 32 forwardly (to the left in FIGS. 17 and 18). The tiles 32 may be backed up by a suitable block 171 to keep them erect on the belts 170. Thebelts 170 extend between idler pulleys 172 and drive pulleys 173 that are mounted on a shaft 174 that is coupled by a drive chain 175 and a gearbox 176 to a motor 177.

Secondary feeding'belts 178 are engaged in drive pulleys 179 also keyed or pinned on the shaft 174 and lead forwardly therefrom being engaged with idler pulleys 179 at their forward ends. The secondary feeding belts 178 are spaced inwardly from the first feeding belts 170 and high speed idlers 180 are mounted with the idler pulleys 179 on an idler shaft 181. The ends of the secondary feeding belts 178 are spanned by high speed feeding belts 182 engaged with the high speed idlers 180 and driven from drive pulleys 183 which are keyed or pinned on a high speed drive shaft 184. The drive shaft 184 is driven at a speed higher than that of the shaft 174 by a suitable drive motor 185.

When the motors 177 and 185 are energized in response to a signal, the slow speed belts 170 feed the tiles 32 slowly for- .ward with the tiles 32 standing on edge until their lower edges engage the high speed feeding belts 182 which, as can be seen in FIG. 18, successively moves the lower edges of the tiles 32 forwardly causing them to lie flat on the high speed feeding belts 182.

A carrier plate feeding mechanism, generally indicated by the reference number 186, extends across the front end of the tile supply table 169 in order to supply carrier plates 125 as needed to receive groups of twelve tiles 32 that are fed off the high speed belts 182. The carrier plate feeding mechanism comprises a plurality of conveyor rollers 187 mounted in a table generally indicated by the reference number 188 and a plate feeding hopper 189 erected above the rollers 187. A chain driver feeding pall 190 is mounted for reciprocation horizontally across the table 188, being attached to a drive chain 191 that is, in turn, actuated by a reversible motor 192. The drive pall 190 comprises a slide 193. and a finger 194 pivotally mounted on the front of the slide 193. A spring 195 holds the finger 194 vertically erect against a stop 196. When the feeding pall 190 is moved from the dotted line position at the right of FIG. 20 across the table 188, its finger 194 engages the lowermost one of the carrier plates 125, sliding it out of the hopper l89 and moving it on the table rollers 187 until the leading edge of the particular carrier plate 125 engages a transverse rail 197. This position of the carrier plate 125 is in alignment with the ends of the tile guide chutes 168. A depending actuator 198 closes a micro switch 199 which energizes the tile belt feeding motors 177 and 185 through a timer 200, to insure the continued movement of the tile feeding belts 170 and 182 for a length of time sufiicient for the twelve tiles to be moved onto the respective carrier plate 125.

The micro switch 199 also actuates the reverse coils of the motor 192 resulting in the backward movement of the chain 191 to carry the board feeding pall 19 from the solid line position in FIG. 20 back to the dotted line position at the right of FIG. 20. When the pall 190 reaches the position at the right of FIG. 20 its switch actuator 198 engages a second micro switch 201 resetting the circuit to the chain feeding motor 192 for forward feed and establishing a circuit to initiate the feeding of the next carrier plate 125. p

A light cell 202 directs a beam of light through the space occupied by one of the carrier plates 125 in tile receiving position (FIG. 20). When an operator at the position indicated by the block numbered II lifts a loaded carrier plate 125 off of the table 128, the light beam strikes a photoelectric cell 203 and signals the carrier plate feeding motor 192 to move the next one of the carrier plates 125 into tile receiving position.

The operator then places the loaded carrier plate 125 in the position determined by the boundary plates 25 and 26 and carries out the method of the invention in order to place the masses 33 of binding medium on the backs of the tiles 32 as described above.

The conveyor 31 (see FIG. 17) leads away from the table 20 to a position for a third operator, indicated by the square labeled III, carrying the stacks of tile groups 29 to a packaging station generally indicated by the reference number 204. At this point operator III removes the top plate 129 from the stack of tile groups 29 and packages the tile sheets or groups 29 in a suitable carton. At the same time operator Ill removes the carrier plates 125 which have been functioning as interplanes in the stack of tile groups 29, and places them on a conveyor mechanism generally indicated by the broken lines labeled 205 for return to the carrier plate feeding mechanism 186. I

Having described my invention I claim;

1. A method for assemblying a plurality of groups of flat modular pieces, said pieces being of such sizes and shapes that when arranged in pre-selected spacing each group has a predetermined plan configuration and comprises a selected number of pieces of predetermined shape and occupies a predetermined area, said pieces having parallel front and back major faces and edge surfaces extending therebetween, said method comprising:

. establishing a vertically extending boundary of sufficient extent along the border of an assembly so as to fix the position of said group of pieces forming an assembly when said group is positioned in contact with said boundary;

2. assembling said group of a selected number of pieces with their front faces lying in a base plane normal to said boundary with the border of said group extending along said boundary and the pieces comprised by said group in preselected arrangement;

3. moving said pieces into preselected space positions relative to each other;

4. placing a mass of binding medium along at least portions of the adjacent edges of the back surfaces of each adjacent pair of individual pieces in said group and extending partially along and across the inter-piece spaces therebetween;

40 said binding medium being capable of wetting and bonding to the edges of the back surfaces of said pieces and to the contiguous portions of the edge surfaces of said pieces;

5. placing a flat inflexible inter-plane over the back surfaces of said pieces, said inter-plane including a surface in contact with said masses of binding medium which is nonwettable by said binding medium;

6. translating said inter-plane in a direction normal to the plane of the faces of said pieces to press said masses of binding medium in such normal direction, forcing at least some of the medium in said masses into the inter-piece spaces across which said masses extend and flattening the back surfaces of all of said masses into a common plane parallel to the plane of the faces of said pieces;

7. repeating the steps of assembling and moving groups of said pieces to provide successive assemblies and spreading binding medium, placing inter-planes thereupon for building up a stack of superposed assemblies of the same plan configuration, whereby the upper surface of each of said inter-planes acts as a base plane for the front faces of a successive group of said pieces; and

8. setting up said masses of binding medium to a condition where it bonds tightly to said pieces, bridges the spaces therebetween and is flexible at temperatures encountered in shipping and installing said assemblies.

2. A method according to claim'] in which the inter-planes have a plan configuration at least equal to the plan configuration of the assemblies of pieces placed thereon.

3. A method according to claim 1 for the assembly of pieces having protuberances on their back major faces all terminating in a common plane and in which the back surfaces of the masses of binding medium are all flattened into the common plane of said protuberances.

4. A method according to claim 1 for the assemblyof pieces having mutually engageable laterally protruding spacers for establishing inter-piece spacing and the binding medium is forced into the inter-piece spaces between said spacers.

5. A method according to claim 1 in which the vertical boundary is established by erecting two verticalplanes that intersect along a vertical line at an angle corresponding to the angle of intersection of lines drawn along adjacent edges of the assembly to be fabricated.

6. A method according to claim 1 in which the binding medium is fluid at room temperature and sets up after exposure to air for a period of time.

7. 'A method according to claim 1 in which the binding medium is placed on the back surfaces of the pieces by being fed thereto in a measured quantity through a plurality of distribution passages in a manifold plate which passages lead to downwardly opening, elongated orifices that are oriented according to and overlie the inter-piece spaces and have lengths less than the lengths of the adjacent edges of the pieces which they overlie, whereby a single measured charge of medium is evenly distributed to all of said nozzles and the masses of binding medium placed on the back surfaces of said pieces are substantially identical in plan dimensions and volume.

8. A method for assembling a plurality of groups of flat modularpieces, said pieces being of such sizes and shapes that when arranged in pre-selected spacing each group has a predetermined plan configuration and comprises a selected number of pieces of predetermined shape, and occupies a predetermined area, said pieces having parallel front and back major faces and edge surfaces extending therebetween, said method comprising:

l. establishing a vertically extending boundary of sufficient extent around the border of an assembly so as to fix the position of said group of pieces forming an assembly when said group is moved horizontally into contact with said boundary;

2. assembling said group of a selected number of pieces with their front faces lying in a base normal to said boundary with the border of said group extending along said boundary and the pieces comprised by said group in preselected arrangement; 7

3. moving said pieces into preselected spaced positions relative to each other;

4. placing a mass of binding medium along at least portions of the adjacent edges of the back surfaces of each adjacent pair of individual pieces in said group and extending partially along and across the central portion of interpiece spaces therebetween;

4a said binding medium being capable of wetting and bonding to the edges of the back surfaces of said pieces and, to the contiguous portions of the edge surfaces of said pieces;

5. placing a sheet of material that is non-wettable by said binding medium nor to which said binding medium bonds, onto and. extending horizontally over the backs of the masses of binding medium;

6. placing a relatively inflexible inter-plane on said nonwettable sheet for establishing a second base plane;

7. translating said inter-plane to a position parallel to and at a fixed distance from the base plane of the front faces of said pieces;

8. repeating the steps of assembling and moving groups of said pieces to provide successive assemblies and spreading binding medium, placing non-wettable sheets and placing inter-planes thereupon for building up a stack of superposed assemblies of the same plan configuration, whereby the upper surface of each of said inter-planes acts as a base plane for the front faces of a successive group of said pieces;

9. placing a weight on top of the uppermost one of said non- 

1. A method for assemblying a plurality of groups of flat modular pieces, said pieces being of such sizes and shapes that when arranged in pre-selected spacing each group has a predetermined plan configuration and comprises a selected number of pieces of predetermined shape and occupies a predetermined area, said pieces having parallel front and back major faces and edge surfaces extending therebetween, said method comprising:
 1. establishing a vertically extending boundary of sufficient extent along the border of an assembly so as to fix the position of said group of pieces forming an assembly when said group is positioned in contact with said boundary;
 2. assembling said group of a selected number of pieces with their front faces lying in a base plane normal to said boundary with the border of said group extending along said boundary and the pieces comprised by said group in preselected arrangement;
 3. moving said pieces into preselected space positions relative to each other;
 4. placing a mass of binding medium along at least portions of the adjacent edges of the back surfaces of each adjacent pair of individual pieces in said group and extending partially along and across the inter-piece spaces therebetween; 4a said binding medium being capable of wetting and bonding to the edges of the back surfaces of said pieces and to the contiguous portions of the edge surfaces of said pieces;
 5. placing a flat inflexible inter-plane over the back surfaces of said pieces, said inter-plane including a surface in contact with said masses of binding medium which is non-wettable by said binding medium;
 6. translating said inter-plane in a direction normal to the plane of the faces oF said pieces to press said masses of binding medium in such normal direction, forcing at least some of the medium in said masses into the inter-piece spaces across which said masses extend and flattening the back surfaces of all of said masses into a common plane parallel to the plane of the faces of said pieces;
 7. repeating the steps of assembling and moving groups of said pieces to provide successive assemblies and spreading binding medium, placing inter-planes thereupon for building up a stack of superposed assemblies of the same plan configuration, whereby the upper surface of each of said inter-planes acts as a base plane for the front faces of a successive group of said pieces; and
 8. setting up said masses of binding medium to a condition where it bonds tightly to said pieces, bridges the spaces therebetween and is flexible at temperatures encountered in shipping and installing said assemblies.
 2. assembling said group of a selected number of pieces with their front faces lying in a base normal to said boundary with the border of said group extending along said boundary and the pieces comprised by said group in preselected arrangement;
 2. assembling said group of a selected number of pieces with their front faces lying in a base plane normal to said boundary with the border of said group extending along said boundary and the pieces comprised by said group in preselected arrangement;
 2. A method according to claim 1 in which the inter-planes have a plan configuration at least equal to the plan configuration of the assemblies of pieces placed thereon.
 3. A method according to claim 1 for the assembly of pieces having protuberances on their back major faces all terminating in a common plane and in which the back surfaces of the masses of binding medium are all flattened into the common plane of said protuberances.
 3. moving said pieces into preselected space positions relative to each other;
 3. moving said pieces into preselected spaced positions relative to each other;
 4. placing a mass of binding medium along at least portions of the adjacent edges of the back surfaces of each adjacent pair of individual pieces in said group and extending partially along and across the central portion of inter-piece spaces therebetween; 4a said binding medium being capable of wetting and bonding to the edges of the back surfaces of said pieces and to the contiguous portions of the edge surfaces of said pieces;
 4. placing a mass of binding medium along at least portions of the adjacent edges of the back surfaces of each adjacent pair of individual pieces in said group and extending partially along and across the inter-piece spaces therebetween; 4a said binding medium being capable of wetting and bonding to the edges of the back surfaces of said pieces and to the contiguous portions of the edge surfaces of said pieces;
 4. A method according to claim 1 for the assembly of pieces having mutually engageable laterally protruding spacers for establishing inter-piece spacing and the binding medium is forced into the inter-piece spaces between said spacers.
 5. placing a flat inflexible inter-plane over the back surfaces of said pieces, said inter-plane including a surface in contact with said masses of binding medium which is non-wettable by said binding medium;
 5. A method according to claim 1 in which the vertical boundary is established by erecting two vertical planes that intersect along a vertical line at an angle corresponding to the angle of intersection of lines drawn along adjacent edges of the assembly to be fabricated.
 5. placing a sheet of material that is non-wettable by said binding medium nor to which said binding medium bonds, onto and extending horizontally over the backs of the masses of binding medium;
 6. placing a relatively inflexible inter-plane on said non-wettable sheet for establishing a second base plane;
 6. translating said inter-plane in a direction normal to the plane of the faces oF said pieces to press said masses of binding medium in such normal direction, forcing at least some of the medium in said masses into the inter-piece spaces across which said masses extend and flattening the back surfaces of all of said masses into a common plane parallel to the plane of the faces of said pieces;
 6. A method according to claim 1 in which the binding medium is fluid at room temperature and sets up after exposure to air for a period of time.
 7. translating said inter-plane to a position parallel to and at a fixed distance from the base plane of the front faces of said pieces;
 7. repeating the steps of assembling and moving groups of said pieces to provide successive assemblies and spreading binding medium, placing inter-planes thereupon for building up a stack of superposed assemblies of the same plan configuration, whereby the upper surface of each of said inter-planes acts as a base plane for the front faces of a successive group of said pieces; and
 7. A method according to claim 1 in which the binding medium is placed on the back surfaces of the pieces by being fed thereto in a measured quantity through a plurality of distribution passages in a manifold plate which passages lead to downwardly opening, elongated orifices that are oriented according to and overlie the inter-piece spaces and have lengths less than the lengths of the adjacent edges of the pieces which they overlie, whereby a single measured charge of medium is evenly distributed to all of said nozzles and the masses of binding medium placed on the back surfaces of said pieces are substantially identical in plan dimensions and volume.
 8. A method for assembling a plurality of groups of flat modular pieces, said pieces being of such sizes and shapes that when arranged in pre-selected spacing each group has a predetermined plan configuration and comprises a selected number of pieces of predetermined shape, and occupies a predetermined area, said pieces having parallel front and back major faces and edge surfaces extending therebetween, said method comprising:
 8. setting up said masses of binding medium to a condition where it bonds tightly to said pieces, bridges the spaces therebetween and is flexible at temperatures encountered in shipping and installing said assemblies.
 8. repeating the steps of assembling and moving groups of said pieces to provide successive assemblies and spreading binding medium, placing non-wettable sheets and placing inter-planes thereupon for building up a stack of superposed assemblies of the same plan configuration, whereby the upper surface of each of said inter-planes acts as a base plane for the front faces of a successive group of said pieces;
 9. placing a weight on top of the uppermost one of said non-wettable sheets whereby the mass of said superposed assemblies and weight forces a quantity of said binding medium into the inter-piece spaces and flattens the tops of the masses of binding medium on each assembly to a common plane defined by the surface of the next superposed inter-plane; and
 10. setting up said binding medium to a condition where it bonds tightly to said pieces, bridges the spaces therebetween and is flexible at temperatures encountered in shipping and installing said assemblies. 